Genome-wide identification of oleosin family and expression analysis in response to abiotic stresses in balloon flower [Platycodon grandiflorus]

Oleosins (OLEs) are structural proteins commonly found within oil bodies (OBs), playing a significant role in regulating the number, size, and stability of OBs. Therefore, this study aims to comprehensively analyze the OLE family in balloon flower [Platycodon grandiflorus] - a significant medicinal plant. Through genome-wide exploration and bioinformatics analyses, we identified and characterized five putative OLE proteins from P. grandiflorus (PlgOLEs). This study provides a comprehensive overview of this gene family in balloon flowers, including phylogenic analysis, conserved motifs, isoelectric points, and hydrophobicity. The study revealed the presence of central hydrophobic regions with a proline knot motif, a characteristic feature shared by OLE proteins in various plant species. Additionally, tissue-specific expression analysis revealed that PlgOLEs were predominantly expressed in seeds, indicating their crucial role in seed OB stability. Furthermore, expression profiling under abiotic stresses demonstrated that PlgOLEs are stress-inducible genes, suggesting their diverse physiological functions in stress responses. These findings shed light on the functional diversity of OLEs in balloon flowers and establish a basis for further research, including genetic modification studies, to elucidate their physiological roles.